Directional-ionizing energy emitting implant

ABSTRACT

The directional-ionizing energy emitting implant is for attachment either to natural tissue or a prosthetic device, and delivers a prescribed dosage of energy to targeted tissue. The insert device includes an energy-source material within the insert device that delivers the prescribed dosage of energy to the targeted tissue, while minimizing exposure of nontargeted tissue. The targeted tissue has a known energy-response profile and is adjacent to the targeted tissue. The energy-source material in combination with the prosthetic device defines an actual energy-delivery distribution field. The energy-delivery distribution field has a configuration similar to the known energy-responsive profile of the targeted tissue. The prescribed dosage of energy is applied from energy-source material within the insert device and directed to the targeted tissue. The prescribed energy dosage is determined by using known characteristics of the energy-source material, and by the placement of the energy-source material relative to the targeted tissue. The implant system reduces any occurrence of heterotopic ossification caused by the implant, inhibits growth or migration of benign or malignant living cells, and minimizes or even eliminates infectious processes or delayed keloid or scar formation induced from surgical placement of a functional prosthesis or fixation device, in tissue within or about the device due to its targeted therapeutic energy emission effects.

FIELD OF USE

The present invention relates to an implanted apparatus having an insertdevice that is additive to or the replacement for an anatomic bodystructure or joint for the purpose of delivering a prescribed dosage ofenergy to targeted tissue to inhibit growth or migration of benign ormalignant living cells and to minimize or even eliminate infectious orinflammatory processes, scarring, and fibrosis in tissue within or aboutthe device due to its targeted energy effects.

BACKGROUND OF THE INVENTION

Total or partial prosthetic replacements are now common orthopedicsurgical procedures. As the age of the general population increases, thenumber of such replacements is also increasing. Common symptomsgenerally can be caused by progressive degenerative osteoarthritis,prior localized trauma, previous local surgical procedures within theregion, ankylosing spondylitis, and idiopathic skeletal hyperostosis.

A common delayed complication following such replacements is thedevelopment of heterotopic ossification within or about the adjacentsoft tissue and the prosthesis between the adjoining bone tissue. Thiscomplication results from excessive migration, replication, ordifferentiation of local primitive mesenchymal cells which arestimulated by the surgical trauma. These cells undergo subsequentmetabolic and cytologic metamorphosis to become more specializedosteoblastic cells. These osteoblastic cells then produce osteoid whichis eventually transformed into calcified deposits or bone tissue, but inundesirable locations.

Heterotopic ossification causes varying degrees of debilitating pain,functional or mobile impairment, and increases the likelihood of repeatprocedures after a period of time from several months to a few years.Between 30 and 35 percent of all untreated patients undergoing total hipprosthesis develop some degree of functional impairment or progressivediscomfort, often from heterotopic ossification.

It has been shown in our U.S. Pat. No. 6,120,540 that a radio prosthesiscomprising a prosthetic device and a radio source material that is partof the prosthesis device has utility, for example, in a total hipreplacement. The radio prosthesis is precalibrated to deliver fordosage, dose rate, and depth dose to adjacent target tissue to inhibitgrowth. Such radiation begins its effective delivery immediately at thetime of the procedure and over the immediate critical time frame forheterotopic ossification formation. Since the radiation only travels ashort distance to the targeted area, there is minimal exposure ofradiation to medical personnel and healthy tissue within the patient.The dosage eventually decays to a non-radioactive state thereby enablinghealing without functional impairment to the prosthesis. No separateremoval procedure is required. The patient is discharged upon recoveryand receives the equivalent radiation benefit of several fractionatedexternal beam treatments without the time, inconvenience, discomfort,and expense of conventional radio therapy.

External beam irradiation has established therapeutic effectiveness.When such therapy is delivered within a narrow period of time, theprophylactic use of external beam radiation therapy has been shown toeffectively reduce the incidence and severity of heterotopicossification. A limited, relatively low-dose of focal ionizing radiationto the specific target tissue, when administered predominantly in thefirst several hours to two days after surgery has proven beneficialclinical results with virtually no side effects.

Other relevant art includes the following:

-   -   U.S. Pat. No. 5,681,289 (Wilcox et at) is a system for        dispensing a liquid chemical agent, such as an antibiotic,        anesthetic, growth factor, hormone, anti-neoplastic agent into a        site of a surgical procedure. The system includes at least one        bladder with an internal cavity that connects to an open tube        through which the liquid chemical agent is passed, under        pressure, into the bladder. The bladder is shaped to fit between        a prepared bone section and a prosthesis. The bladder is        connected by a tube to a reservoir and pump.    -   U.S. Pat. No. 4,936,823 (Colvin et al) is an implant capsule for        insertion into a body canal of a patient to apply radiation        treatment to a selected portion of the body canal. The        transendoscopic implant capsule is transported through the body        canal to apply a therapeutic radiation to a tumor within the        patient. The implant capsule is remotely implanted and retrieved        with a fiber optic bronchoscope.    -   U.S. Pat. No. 5,833,593 (Liprie) is a flexible wire for        providing a radioactive source to maneuver through a tortuous        narrow passage to a treatment site within the patient. The        source wire includes an elongated flexible housing tube with a        treatment end modified to receive a radioactive core.

While U.S. Pat. No. 5,728,136 (Thal) discloses a spike member forinsertion into a bone mass, we are unaware of any such device being usedto delivery energy treatment to targeted tissue. External beam radiationtherapy is often not prescribed because of the time required for set-upand treatment, the availability of single fraction treatments andvariations in prescribed dose, patient discomfort and side effects, theneed to irradiate tissue outside the target field, and economicconsiderations. In addition, many patients are not considered forradiation treatment until late in the recovery process, which furtherlimits treatment options.

What is needed is a process and structure for providing the radiationdose originating from an internal site to the targeted tissue, wherebythe emission profile more closely matches the profile of the targetedtissue; a process and a structure that can be readily adapted for anysurgical bone tissue replacement or additive procedures; a process and astructure that is easy to administer, safe for the patient, effectivelyreducing side effects caused by such surgical procedures; and, a processand struct6ure for eliminating the need for separate post-operativetreatment while dramatically (a) reducing any occurrence of heterotopicossification, and (b) minimizing infectious processes in tissue withinor about the device and excessive, restriction fibroid and scarring atthe incision or closure site due to its targeted radiation effects.

SUMMARY OF THE INVENTION

The needs set forth above are addressed by the directional-ionizingenergy emitting implant system and process of the present invention.While the implant system of the present invention is discussed herein inrelationship to the delivery of radiation to targeted tissue, one havingordinary skill in the art will readily appreciate the application of theprinciples of the present invention to other forms of ionizing energydelivery, including but not limited to luminescent energy, hyperthermicenergy, and photo-light energy emission forms.

External beam irradiation establishes therapeutic effectiveness. Thedirectional-ionizing energy emitting implant device of the presentinvention is for attachment either to natural tissue or a prostheticdevice, and delivers a prescribed dosage of energy to targeted tissue.The implant device includes an energy-source material that delivers theprescribed dosage of energy to the targeted tissue, while minimizingexposure of nontargeted tissue. The targeted tissue has a known profileand is adjacent to the targeted tissue. The energy-source material incombination with the prosthetic device defines an actual energy-deliverydistribution field. The energy-delivery distribution field has aconfiguration similar to the known profile of the targeted tissue. Theprescribed dosage of energy is applied from energy-source materialwithin the insert device and directed to the targeted tissue. Theprescribed energy dosage is determined by using known characteristics ofthe energy-source material, and by the placement of the energy-sourcematerial relative to the targeted tissue. The implant system reduces theoccurrence of heterotopic ossification caused by the implant, inhibitsgrowth or migration of benign or malignant living cells, and minimizesor even eliminates infectious processes or delayed keloid or scarformation induced from surgical placement of a functional prosthesis orfixation device, in tissue within or about the device due to itstargeted radiation effects.

The present invention is a directional-ionizing energy emitting implantdevice and a method for delivering a dosage of radiation to targetedtissue. The system comprises a prosthetic device that functionallyreplaces or is additive to a body structure or joint, and radio sourcematerial. The radio source material is positioned either on or withinthe prosthetic device. The actual radiation delivery distribution fieldhas a similar configuration to the profile of the targeted tissue. Theimplant system is particularly useful to minimize or even eliminateinfectious or inflammatory processes or delayed keloid or scar formationinduced from surgical placement of a functional prosthesis or fixationdevice in tissue within or about the device due to its targetedradiation effects.

When such therapy is delivered within a narrow period of time, theprophylactic use of external beam radiation therapy demonstrates aneffective reduction of the incidence and severity of heterotopicossification. A limited, relatively low-dose of focal ionizing radiationto the specific target tissue, when administered predominantly in thefirst several hours to two days after surgery has proven beneficialclinical results with virtually no short or long term side effects.

Additional indications for the use of localized, relatively modest,cumulative radiation doses of approximately 600 cGY to 3500 cGy, havedemonstrated clinical success in providing some bacteriocidal,bacteriostatic, and sterilizing benefits for living tissue. In addition,similar dose applications inhibit keloid excess scar formation. Suchkeloid formation at the skin or sub-dermal tissue within or about asurgical scar or injury can cause significant restriction of motion,dys-mobility, pain, or decreased aesthetic appearance.

Ionizing-type radiation exposure is also routinely used in various waysto sterilize and leukocytic reduce blood products from infectious andimmunoreactive agents in dose ranges of 1500 to 2500 cGy or more,depending upon the method of fractionation and dose rate and type ofenergy administration.

The directional-ionizing energy emitting implant device and method ofthe present invention offer numerous medical, safety and economicadvantages over conventional radiotherapy. The structure of this systemdramatically improves the delivery of the radiation to the targetedtissue as compared with the non-targeted tissue, inherentlyaccommodating for individual patient differences in morphology. Improvedradiation efficacy is achieved by delivering a continuous dose rate ofradiation and by utilizing known characteristics of various radionuclides; such as half-life, specific activity, specific concentration,and type of energy decay.

The artificially implanted apparatus is functionally replacing or isadditive to a normal anatomic body structure or joint. The apparatus isimplanted, imbedded, or contained in a housing for strategicallylocalized solid, liquid, gel-like, gaseous, or other intermediate phaseradio-emitting substance or capable of inducing ionizing radiation,phosphorescence, luminescence, or fluorescence; whereby a precalibratedgeneral or specific total dose, dose rate, or depth dose is delivered toadjacent target tissue to inhibit growth, migration, or differentiationof benign or malignant living cells; to inhibit heterotopicossification; and to minimize infectious or inflammatory processes orminimize delayed scar or keloid formation in such tissue.

Since the radiation only travels a short distance within the patient'ssoft tissue and essentially only through the targeted area, there isminimal radiation risk to medical personnel and healthy tissue withinthe patient. Such radiation may begin its effective delivery immediatelyat the time of the procedure or is activated in delay post-operativelyand over the immediate critical time frame for heterotopic ossificationformation and/or minimize infectious, inflammatory, or scarringprocesses in such tissue. The radio nuclide dosage eventually decays toa non-radioactive state thereby enabling healing and without functionalimpairment to the prosthesis or fixation devices. The patient isdischarged after recovery and receives the equivalent radiation benefitof several fractionated external beam treatments without the time,inconvenience, discomfort, and expense of conventional radiotherapy,while minimizing exposure to nontargeted tissue. Also, the system andmethod of the present invention promote more routine use of prophylacticradiation to prevent heterotopic ossification and minimize infectious,inflammatory, or scarring processes in such tissue by enabling potentialbroader physician access, flexible treatment judgments, and less patientpain and inconvenience.

While the directional-ionizing energy emitting implant system of thepresent invention is discussed herein in relationship to hip-joint, itis to be appreciated by one having ordinary skill in the art that thistechnology is also applicable to total or partial joint replacement, andinjury or fracture fixation, such as a total or partial hip, knee,shoulder, or elbow prosthesis. For purposes of discussion herein, unlessthe context suggests otherwise, a hip replacement is used for purpose ofillustration only. The radiation delivery system of the presentinvention induces the emission of specific radio nuclides enabling theanatomic configuration of the implant, the controlled placement positionof one or more radio nuclides, and the selection of the type orcomposition of the radio source material to deliver a confined andtargeted tissue deposition of ionizing radiation to a pre-calibrateddose rate, depth dose, and total delivered dose of prescribed radiation.

For a more complete understanding of the directional-ionizingenergy-emitting implant of the present invention, reference is made tothe following detailed description and accompanying drawings in whichthe presently preferred embodiments of the present invention are shownby way of example. As the invention may be embodied in many formswithout departing from spirit of essential characteristics thereof, itis expressly understood that the drawings are for purposes ofillustration and description only, and are not intended as a definitionof the limits of the invention. Throughout the description, likereference numbers refer to the same component throughout the severalviews.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an assembly view of a first preferred embodiment of adirectional-ionizing energy emitting implant device of the presentinvention, the implant device being a spike for placement into a hipjoint, the view of the spike being enlarged relative to the hip joint,the hip joint including a bone fixation port for receiving and securingthe spike, the spike including a detachable cap, radio nuclide materialsunder the cap, the cap member being detachable once surgically placedwithin the hip joint;

FIG. 2 is an assembly view of a second preferred embodiment of thedirectional-ionizing energy emitting implant device of the presentinvention for retention relative to a hip joint, the implant devicebeing enlarged relative to the hip joint, the insert member including anengageable locking clasp to secure the insert member relative to the hipjoint once implanted;

FIG. 3 is an assembly view of a third preferred embodiment of a pair ofdirectional-ionizing energy emitting implant devices of the presentinvention for retention into a hip joint, the hip joint including afixation plate for stabilizing the fractured hip joint, the hip jointincluding ports for accepting the pair of implant devices, the implantdevices having externally identifiable demarcations necessary toproperly provide distance, orientation, and alignment;

FIG. 4 is an assembly view of another preferred embodiment of adirectional-ionizing energy emitting implant device of the presentinvention, one of the implant devices having an external catheteradaptation and a modified catheter component, the external catheterbeing implanted at the time of surgery, the external catheter adaptationproviding a delivery conduit for placement of the implant device, themodified catheter component having indwelling, activatible energymaterials, the modified catheter elongated portion internal channels;and

FIG. 5 is an assembly view disclosing a fifth preferred embodiment of adirectional-ionizing energy emitting implant device of the presentinvention, the implant devices being implanted within the femur andtibia, for providing energy from the implant devices to targeted tissueabout the knee.

MODES FOR CARRYING OUT THE INVENTION

The implant of the present invention is useful in applications involvingthe replacement or addition of bone tissue. The radiation deliverysystem induces the emission of specific radio nuclides enabling theanatomic configuration of the implant, the controlled placement positionof one or more radio nuclides, and the selection of the type orcomposition of the radio source material to deliver a confined andtargeted tissue deposition of ionizing radiation to a pre-calibrateddose rate, depth dose, and total delivered dose of prescribed radiation.

Referring now to the drawings, FIG. 1 is an assembly view of a firstpreferred embodiment of a implant or insert member [15] of the presentinvention, the insert member [15] being a spike or insert member [15]for placement into a hip joint [22], the view of the spike or insertmember [15] being enlarged relative to the hip joint [22], the hip joint[22] including a bone fixation port [26] for receiving and securing thespike or insert member [15], the spike or insert member [15] including adetachable cap portion [23], radio nuclide materials under the capportion [23], the cap portion [23] member being detachable oncesurgically placed within the hip joint [22].

The insert member [15] is for attachment either to organic tissue or aprosthesic device [20], and delivers a prescribed dosage of radiation totargeted tissue. The insert member [15] includes an radio sourcematerial within the insert member [15] delivers the prescribed dosage ofradiation to the targeted tissue, while minimizing exposure ofnontargeted tissue. The targeted tissue has a known radio response andsensitivity profile and is adjacent to the targeted tissue. Theradio-source material in combination with the prosthesic device [20]defines an actual radiation-delivery distribution field. Theradiation-delivery distribution field has a configuration similar to theknown radio response and sensitivity profile of the targeted tissue. Theprescribed dosage of radiation is applied from radio-source materialwithin the insert member [15] and directed to the targeted tissue. Theprescribed radiation dosage is determined by using known characteristicsof the radio-source material, and by the placement of the radio-sourcematerial relative to the targeted tissue. The implant system reduces theoccurrence of heterotopic ossification caused by the implant, inhibitsgrowth or migration of benign or malignant living cells, and minimizesor even eliminates infectious and inflammatory processes or delayedkeloid or scar formation induced from surgical placement of a functionalprosthesis or fixation device, in tissue within or about insert member[15] due to its targeted radiation effects.

The radio nuclide materials include but are not limited to solids,particles, gels, liquids, or gas radio nuclide materials for therapy.The insert member [15] comprises a cap portion [23] and an elongatedportion [24]. The cap portion [23] of the insert may either bedetachable or integral with the insert member [15]. The elongatedportion [24] projects into and locks into bone tissue or prosthesicdevice [20]. The insert member [15] may also be an anchor, a plate, ascrew or other device that is attachable to organic tissue—such as bone,cartilage, or the like. The insert member [15] may also be secured to aprosthesic device [20].

Extending outward from the elongated portion [24] of the insert member[15] is a projection. The projection is preferably made of titanium orother alloy metal. The projection is initially closed and becomesengaged once inserted into the bone tissue. The bone tissue includes abone-fixation port [26], the port [26] being drilled or nailed to adepth of a few millimeters to centimeters. The bone ports [26] used forspike or insert member [15] retention may be activated outward from adisengaged, internal position from the cap portion [23] of the insertmember [15], or from an internally placed energy-emitting component thatis placed and locked.

The radio nuclide material is preferably loaded into the cap portion[23] of the insert member [15] prior to implant, but may also be loadedafter implant is completed. The radio nuclide material may be eitherintegral with the cap portion [23] or attachable therewith. In onepreferred embodiment, the emitting radio-seed, radio-wire, orradio-pellets are placed into the cap portion [23] of the insert member[15] prior to implant.

Disposed on the undersurface of the cap portion [23] is a bone surface“attenuating” shield component. This shield [29] is designed to minimizeexpose of nontargeted tissue. Directional emission of energy to thetarget tissue is provided by the external shape of the insert member[15], the type of materials employed.

FIG. 2 is an assembly view of a second preferred embodiment of thedirectional-ionizing energy emitting implant or insert member [15] ofthe present invention for retention relative to a hip joint [22], theinsert member [15] being enlarged relative to the hip joint [22], andthe insert member [15] including an engageable locking clasp to securethe insert member [15] relative to the hip joint once implanted.

The top surface of the insert member [15] is preferable a removableradio-protection tape or covering. Disposed within a fixed or attachabletop of the cap portion [23] of the insert member [15] are radio nuclidechannels, pockets, or reservoirs. Also, disposed in the cap portion [23]of the insert member [15] is an injectable or external access port [26]to place the radio nuclide materials. The top of insert member [15]abuts the outer surface of the bone tissue. The depth placement canalsin the bone ports [26] are preferably drilled to a depth of between 5and 15 mm.

Disposed on the undersurface of the cap portion [23] of the insertmember [15] is a radio-attenuating shield [29] or a magnetized elementto shift radio-emission of the charged particles. A plurality ofengageable, locking clasps are disposed proximate to the cap portion[23] on the elongated portion [24] of the insert member [15].

Underneath the removable top of the cap portion [23] of the insertmember [15] portion are disposed positionally placed radio-opaquemarkers. Localization matching of the cap portion [23] of the insertmember [15] enable alignment, and may comprise markings [35] in the formof labels, demarcations, symbols, that are positionable to prosthesis[20] or insert member [15]. The alignment markers are disposed proximateto a partial or complete acetabular joint prosthesis [20]. The alignmentmarkers are useful for verifying positioning and alignment.

FIG. 3 is an assembly view of a third preferred embodiment of a pair ofdirectional-ionizing energy emitting implants or insert members [15] ofthe present invention for retention into a hip joint, the hip jointincluding ports [26] for accepting the pair of insert members [15], theinsert members [15] having externally identifiable demarcations ormarkings [35] necessary to properly provide distance, orientation, andalignment.

Externally identifiable demarcations or markings [35] that are eithervisible, palpable, or measurable are disposed on the insert member [15]to enable distance, orientation, and alignment for placement of theinsert member [15] in the bone tissue, in relationship to the plates orprosthesis [20], in order to deliver accurate, directional-ionizingenergy emissions or activation.

The hip joint [22] includes a fixation plate secured to the hip-jointfor stabilizing the fractured hip joint. The fixation plate includesfour fasteners. The insert members [15] are retained within spatially,accurately placed radio module ports [26] within the hip.

In another preferred embodiment of the implant device of the presentinvention, the identifiable markings [35] are disposed on the fixationplate, and are either visible, palpable, measurable on the insert member[15] to readily enable matching for alignment purposes for orientation,and distal positioning for the insert member [15].

FIG. 4 is an assembly view of another preferred embodiment of an insertcompatible implant system of the present invention for use in ahip-socket joint [20], one of the insert members [15] having an externalcatheter component [36A] and a modified catheter component [36B], theexternal catheter component [36A] being implanted at the time ofsurgery, the external catheter component [36A] providing a deliveryconduit for placement of the insert member [15], the modified cathetercomponent [36B] having indwelling, activatible energy materials, themodified catheter elongated portion internal channels [31].

An external catheter component [36A] is shown as well as a modifiedcatheter component [36B]. The external catheter component [36A] may beattached at the time of surgery. The catheter may provide either adelivery conduit for permanent or temporary placement of theradio-source materials. In one preferred embodiment, an internaldelivery or detachment wire is used to remove a protective shield, orcovering, and thereby activate effective energy emissions from acontained source.

Emanating for the cap portion [23] of the insert member [15] in adirection away from the pelvic bone section is the radio energy emissionpattern [38A]. The energy source within the insert member [15] is eitherintegral with the insert member [15] or positioned therewithin. The boneport [26] may be drilled, screwed, tapped, hammered, or the like. Thebone ports [26] may also be screws that pop out.

In the modified catheter component [36B], a metallic external energyconductive wire feeds into a external catheter wall. The externalcatheter wall is preferably an insulating polymer carbonate compound.The internal energy conductive source is preferably electrical orelectromagnetic. The insert member [15] of the present invention mayalso be applied with fracture screws, pins, or even plates. Also, otherapplicable joints include but are not limited to the elbow-arm,shoulder, foot-ankle, and the spine.

Disposed within the cap portion [23] of the inset member of the presentinvention is a power source—such as an activatible electrical solenoid,an electromagnet, ultrasound-emitting, high frequency crystals, orresistance-type coil. The insert member [15] is preferably constructedof metal alloys or polycarbonate, plastic, or biodegradable materials.Emanating for the cap portion [23] of the insert member [15] in adirection away from the pelvic bone section are energy wave patterns[38B]. Disposed within the elongated portion [24] of the insert member[15] is one or more internal module anchor channels.

FIG. 5 is an assembly view disclosing a fifth preferred embodiment ofthe directional-ionizing energy emitting implant or insert member [15]of the present invention, the insert members [15] being implanted withinthe femur and tibia, for providing directed energy emission from theinsert members [15] to targeted tissue about the knee for partial orcomplete knee prosthesis. As shown, the insert members [15] arecompatible with partial and complete knee prosthesis—the knee jointincludes tibial plateaus and femoral condyle prosthesis.

There are multiple potential sites for placement of thedirectional-ionizing energy emitting implant, as for example in a kneejoint, to minimize post-surgical delayed scarring, infection, orheterotopic ossification. The insert member [15] of the presentinvention may be implanted directly for partial or complete prosthesisof other joints, including but not limited to the elbow-arm, shoulder,foot-ankle, and the spine. The insert member [15] of the presentinvention may be attachable to prosthesis or implant components orseparately but dependently placed in bone, cartilage, or soft tissue.Retention can also be achieved with fracture screws, pins, anchors,plates or the like.

There are various design structures and ways of incorporation the radiosubstance with a prosthetic apparatus, as well as, methods of deliveringthe radioisotope materials as are hereinafter described.

The therapeutic radiation component is embedded into the prostheticdevice prior to in vivo placement; placed in specific sectionsimmediately prior to surgical implantation, placed after satisfactoryimplantation but prior to wound closure, or injected or cannulated aftersurgical closure, particularly, if a liquid, gel, or gas is the radiosource material.

Gels, liquids, gases, or other inter-phase radio compounds can beloaded, injected, molded, screwed, foamed, mixed, taped or by otherattachment methods and devices either directly or as a preformedradio-contained or measured unit onto or within a separate leadingmodule specific for the prosthesis device or directly to the prostheticapparatus, either before, during or after surgical implantation, withoutthe need of an intermediary loading device.

Although this dose range of radiation has been safely used forheterotopic ossification and to minimize infectious processes in suchtissue with a negligible risk of delayed tumor formation or tissuenecrosis, the prosthesis and femoral head are not exposed to more than aminimal amount of radiation. These are specific sites of desired growthand repair cell migration thereby allowing for stable, permanentintegration of the fixed components of the prosthesis into prepped bone.Patients require formal fluoroscopic simulation and dosimetry planningwith defined fields for delivery of external beam radiotherapy.

Total doses of less than 700 cGy begin to show diminished efficacyversus compromise for any patient comfort or radiation risks.Accordingly, a dose range of 700 to 900 cGy is able to limit heterotopicossification formation rates of clinical significance to between 1 and 9percent.

The radio nuclide component may be any humanly compatible andtherapeutically applicable solid, liquid, gas, gel, or otherintermediate phase radio nuclide or radioisotope compounds which emitgamma rays, x-rays, beta particles, alpha particles, positrons, augerelectrons, photons, or any combination thereof produced by nucleardecay; isomeric transition; electron capture; fluorescent,phosphorescent or luminescent induction; external bombardmentactivation; electrical stimulation or any combination thereof.

Electrical stimulation includes specifically designed or adoptions ofconventional x-ray or electron beam, producing catheters or wires thatare placed into or about the module component or radio prosthesisthereby providing a controlled radiation dose to target tissue withoutnecessarily a radioactive component or element.

The separated or attached module can be designed to optimize directionalalignment of the electrical-produced, short-distance radiation. In onepreferred embodiment of the radio prosthesis device of the presentinvention, a shielded component is used to minimize effective radiationdose to non-targeted, normal tissue. Such a module may be activated atthe time immediately after placement or in delay at recovery or bedside,post-anesthesia. As used herein, “activation” refers to an intendedactive step taken to expose previously placed radio nuclide containingcomponents, or delayed placement into the modules of a radio nuclidesource, or placement via an attached or separated intermediarycatheter-type component such that a portal [26] or complete electricalor light radio-decay generated radiation emitting device may be afterloaded for a finite period of time.

The integrateable or “free-floating” (but specific in position to theprosthesis) modules or temporary or permanent intermediary catheters(for radioactive source, delivery or removal) may be partial orcompletely flexible. Various configuration include shapes such as asmall spike, loop, half-moon, flat, circular, etc.

The separate modules or attachable intermediary components arebiologically safe and dissolved in materials that can intentionallydegrade with time after placement in vivo.

In one preferred embodiment of the system of the present invention, theradio nuclide containing component or the radio-directional component,to which an externally delivered or attached radiation producing unit isattached degrades or dissolves in vivo after the radiotherapy dose isadministered.

The modules or connectable catheters delivering components may beextracted in vivo, in delayed fashion by an externally remainingstring-like attachment, or tabs, reels, or the like, as intentionallyplaced for clinical administration of radiation to stop heterotopicossification, infection or inflammatory risk, or excess scar formationby subsequent removal of the modules or catheters after the radiotherapydose is administered.

Visible markings demarcated as lines, dots, numbers, colors, or acombination of such, with palpable surface changes (such as bumps, roughsurfaces or such) are preferably placed upon the radio prosthesis ormodules or intermediary interchangeable catheter components in order tofacilitate optimal placement, ex vivo or in vivo, in spatialorientation, alignment or matching between each other or the radionuclide-containing component.

Radio-opaque markers composed of metal, metal alloys, radioactivenuclides or related parent or daughter isotopes, etc. are preferablypositioned and fashioned as similar for function and intent as thevisible or palpable markers, except that they provide a visibleconfirmation of the position and orientation of said components by x-rayvia fluoroscopy or hard copy x-ray, or equivalent. This can providemeasurement assessment and 2-dimensional or 3-dimensional positionalidentification of the components, as well as confirmatory calculationsof expected radiation dose to the adjacent tissue.

In still another preferred embodiment of the radio prosthesis device ofthe present invention, a magnetic-property-containing element within theindependent modules, prosthesis, or associated catheter-type componentsis directly or separately attached or integrated or impregnated upon theinternal or external surfaces. The magnetic field inducing material arepreferably made of any known biologically safe heavy metal, metal alloy,or electrically induced magnetic field material (causing field shift ofatomic shell electrons) in order to “directionally shift” electron orbeta particle radiation toward the targeted tissue or repel similarcharged particle energy away from tissue.

Integrated medication, not administered systemically or as aninstillation primary therapy, but one whereby an anti-inflammatory oranti-microbial or anti-scar type compound (i.e. -cortico steriod) isimpregnated onto or within any of the components; or may be added tocomponents later, to minimize complications or tissue reactions inducedfrom the device or components themselves (not for general,regional/systemic treatment).

Specific primary radio nuclides, either in stable or radioactive forminclude but are not limited to xenon, krypton, neon, argon, radon,technetium, rhenium, yttrium, phosphorus, iodine, strontium, samarium,gold, copper, palladium, iridium, tin, rubidium, osmium, platinum,ytterbium, cesium, americium, radium, thallium, chromium, vanadium,barium, titanium, bismuth, and rhodium. More particularly, the specificprimary radio nuclides of choice are yttrium, strontium, iridium,iodine, palladium, cesium or technetium.

The utilization and integration of any of these isotopes are applied tothe device to enhance individual energy emissions and tissuepenetration, in vivo safety, half-life decay properties and specificactivities or concentrations of materials. A near ideal effect on thetarget tissue and depth is thereby achieved with regard to dose rate,depth dose, total does, and elimination rates. The preferred dose ratesdeliver energy in the range of 50 to 250 cGy/hr. Acceptable dose ratesalso include from 10 to below 50 cGy/hr and above 250 to 500 cGy/hr.Dose rates in the order of magnitude of from 10 to 200 cGy/min may be ofbenefit, if the half-life and millicuries of radioactivity can be short(several minutes) and low respectively or radio-material has a shortdwell time and is removed. Dose rates per milticurie are between 0.5cGy/min and 200 cGy/min-mCi.

The total dose delivered to the targeted tissue are preferably between700 cGy and 2000 cGy. Also, an acceptable total dose is from 200 tobelow 700 cGy, and above 2000 to 3500 cGy. The total dose to nontargetedsoft tissue and bone tissue is less than 500 cGy, but even 500 to 1500is acceptable. The radio-dose prescription is precalibrated for eachspecific prosthesis size and application site and marked directly on theprosthesis apparatus. This would be intended to deliver a fixed dose anddose rate range.

Also, a sensor (not shown) may be used to monitor, verify, or controlthe delivery of the prescribed dose of radiation. Emergency release andretrieval elements enable the immediate removal of at least theradioactive component of the prosthesis.

Other sites of use for a radio-implant include all fixed or mobilejoints, compartmental soft tissues and axial or appendicular bones.

Solid or gel-phase compounds may be pre-adhered to the prosthesis byprocesses involving laser techniques, chemical bonding, electro-ionexchange, thermal conditioning, emulsion-type technologies, or emulsionslip coatings. Ion beam bombardment or deposition to reduce adhesions,thrombus, and provide anti-microbial properties may be applied and isnow commercially available from Spire Corp, Bedford, Mass.

Similar methods may be applied to place radio source materials incustomized and fitted loading compartments or modules which areattachable at specific sites on the prosthesis and can be placed priorto, during, or after surgical implantation of the prosthetic device.

In addition, a prefabricated, individualized unit dose of radio sourcematerial may be constructed in generic or customized form similar to aseed, wire, ball, plaque, powder, pellet, etc. or the like and therebyloaded, with then known specific quantities of radiation upon or withinpreviously described attachable modules, units, compartments and thenplaced onto or within the prosthetic device. Likewise, thesepre-measured, precalibrated radio dose units may be placed directly ontoor within the prosthetic apparatus utilizing specifically designedslots, compartments, clips, sections, etc. or the like whereby anintermediary module or loading apparatus is not necessarily required.

The placement of the radio materials may be permanent dwelling,temporary with extraction, or with the option of multiple delayedintroductions or retrieval mechanisms.

Primary materials of the individualized radio-unit loading modules orcompartments, and prosthetic radio components are made from almost anymaterials. The radio components preferably comprise plastics; natural orsynthetic rubbers; metals; metal-alloys; bio-compatible molecular chaincompounds; allogenic or heterogenic natural or synthetic dissolublecompounds when in vivo (natural human, animal, or plant by-productmaterials); viton rubber; polyurethane, polyethylene, polyimide,polyvinylchloride, polyamide, polytetra fluoroethylene, silicone.

Alternative therapy options for heterotopic ossification include use ofnon-steroidal anti-inflammatory drugs such as indomethacin, administeredat various dosing schedules from 8 days to 6 weeks of treatment. Whilethis method of drug therapy has shown some benefit, it is less effectivethan a dosage greater than 700 cGy of irradiation for inhibitingclinically significant (Brooker class II-IV) heterotopic ossification.In addition, many patients experience gastrointestinal-intestinalbleeding or gastritis with this drug, requiring additional medications.Furthermore, routine compliance by all at risk patients may falterthereby leaving an unknown risk of eventual heterotopic ossificationfailure or severity. Both methods offer consideration for optimized,long term outcome.

In yet another preferred embodiment of the implant system of the presentinvention, the insert member [15] is treated with a bacteriocidal andbacteriostatic material that will kill and prevent the growth ofbacteria, viruses, fungi, and the like.

It will be readily apparent to those skilled in the art that theimplementation and mechanization of the system and method of the presentinvention can be varied considerably to improve operation without goingbeyond the bounds of the present invention. For example, a programmeddose can be applied and administered from an implant that is controlledfrom an external source, whereby the emission, the decay rate, theinitiation, duration, intensity, direction is regulated. In addition, asimilar-type device can be mounted on bone tissue and directed atadjacent tissue for treatment, thereby eliminating exposure of healthytissue to the controlled dose.

Throughout this application, various Patents and Applications arereferenced by patent number and inventor. The disclosures of thesePatents and Applications in their entireties are hereby incorporated byreference into this specification in order to more fully describe thestate of the art to which this invention pertains.

It is evident that many alternatives, modifications, and variations ofthe directional-ionizing energy-emitting implant of the presentinvention will be apparent to those skilled in the art in light of thedisclosure herein. It is intended that the metes and bounds of thepresent invention be determined by the appended claims rather than bythe language of the above specification, and that all such alternatives,modifications, and variations which form a conjointly cooperativeequivalent are intended to be included within the spirit and scope ofthese claims.

1. An insert device for implantation and retention to organic tissue fordelivering a prescribed dosage of ionizing energy to targeted tissue,the targeted tissue being adjacent to the organic tissue, the targetedtissue having a known ionizing energy-responsive profile, the insertdevice cooperating with a functioning or stabilizing prosthetic orfixation-type device, an ionizing energy-source material in combinationwith the prosthetic or fixation device defining an actual ionizingenergy-delivery distribution field, the ionizing energy-source materialbeing non-radioactive at time of implantation, the insert deviceincluding the ionizing energy-source material for delivery of theprescribed dosage of ionizing energy to the targeted tissue, theionizing energy-delivery distribution field having a configurationsimilar to the known ionizing energy-responsive profile of the targetedtissue, the prescribed dosage of ionizing energy being applied from theinsert device to the targeted tissue once the prosthetic or fixationdevice has been implanted, the ionizing energy-source material being anon-chemical agent, the prescribed ionizing energy dosage beingdetermined by using known characteristics of the ionizing energy-sourcematerial and by controlling the placement of the ionizing energy-sourcematerial relative to the targeted tissue.
 2. An insert device forimplantation and retention to organic tissue for delivering a prescribeddosage of ionizing energy to targeted tissue, the targeted tissue havinga known ionizing energy-responsive profile, the insert device beingimplanted into the organic tissue, the organic tissue being adjacent tothe targeted tissue, the insert device including an ionizingenergy-source material, the ionizing energy-source material within theinsert device defining an actual ionizing energy-delivery distributionfield, the ionizing energy-source material being non-radioactive at timeof implantation, the ionizing energy-delivery distribution field havinga configuration similar to the known ionizing energy-responsive profileof the targeted tissue, the ionizing energy-source material enabling thedelivery of the prescribed dosage of ionizing energy to the targetedtissue, the prescribed dosage of ionizing energy being directed from theinsert device to the targeted tissue once the insert device has beenimplanted into the organic tissue, the ionizing energy-source materialbeing a non-chemical agent, the prescribed ionizing energy dosage beingdetermined by using known characteristics of the ionizing energy-sourcematerial and by controlling the placement of the ionizing energy-sourcematerial relative to the targeted tissue.
 3. A surgical procedurecomprising: determining a prescribed dosage of ionizing energy that isto be delivered from an insert device to targeted tissue, the targetedtissue having a known ionizing energy-responsive profile, the insertdevice being positioned within the prosthetic or fixation device, theinsert device including an ionizing energy-source material, the ionizingenergy-source material in combination with the prosthetic or fixationdevice defining an actual ionizing energy-delivery distribution field,the ionizing energy-delivery distribution field having a similarconfiguration to the known ionizing energy-responsive profile of thetargeted tissue; introducing the ionizing energy source material intothe prosthetic or fixation device; implanting the prosthetic or fixationdevice into organic tissue during a surgical procedure, the ionizingenergy-source material being selected for delivering a predetermineddosage of the ionizing energy from the ionizing energy-source materialto targeted tissue, the targeted tissue having a known ionizingenergy-responsive profile; activating the ionizing energy-sourcematerial once the insert device has been implanted into the organictissue; and delivering the prescribed dosage of ionizing energy from theionizing energy-source material to the known ionizing energy-responsiveprofile of the targeted tissue.
 4. A surgical procedure comprising:determining a prescribed dosage of ionizing energy that is to bedelivered from an insert device to targeted tissue, the targeted tissuehaving a known ionizing energy-responsive profile, the insert devicebeing affixed to the prosthetic or fixation device, the insert deviceincluding an ionizing energy-source material, the ionizing energy-sourcematerial defining an actual ionizing energy-delivery distribution field,the ionizing energy-delivery distribution field having a similarconfiguration to the known ionizing energy-responsive profile of thetargeted tissue; introducing the ionizing energy-source material intothe insert device; positioning the insert device into organic tissueduring a surgical procedure, the ionizing energy-source material beingselected for delivering a predetermined dosage of the ionizing energyfrom the ionizing energy-source material to targeted tissue, thetargeted tissue having a known ionizing energy-responsive profile;activating the ionizing energy-source material once the insert devicehas been positioned into the organic tissue; and delivering theprescribed dosage of ionizing energy from the ionizing energy-sourcematerial to the known ionizing energy-responsive profile of the targetedtissue.
 5. An implant system for implantation and retention to organictissue for delivering a dosage of ionizing energy to targeted tissue,the system including an insert member secured to a prosthetic orfixation device for implantation and retention to natural bone tissueand adjacent to the targeted tissue, the insert member having anionizing energy-source material that is part of the prosthetic orfixation device that is implanted, the insert device including anionizing energy-source material, the ionizing energy-source materialbeing non-radioactive at time of implantation, the ionizingenergy-source material being a non-chemical agent, the ionizingenergy-source material enabling ionizing energy treatment to thetargeted tissue, the ionizing energy treatment being applied from theinsert member to the targeted tissue after implantation, whereby apredetermined dosage of prescribed ionizing energy to the targetedtissue is determined by using known characteristics of the ionizingenergy-source material and by controlling the placement of the ionizingenergy-source material relative to the targeted tissue.
 6. A surgicalmethod comprising: introducing an insert member into a prosthetic orfixation device, the insert member including an ionizing energy-sourcematerial, the ionizing energy-source material being non-radioactive attime of implantation, the prosthetic or fixation device and ionizingenergy-source material comprising a closed system for implantationwithin a patient, the prosthetic or fixation device having a functionindependent of ionizing energy delivery, the ionizing energy-sourcematerial being selected for delivering a predetermined dosage of theionizing energy from the ionizing energy-source material to targetedtissue within a known ionizing energy-responsive profile, the knownionizing energy-responsive profile of the targeted tissue beingproximate to the implant site; securing the insert member to theprosthetic or fixation device, the ionizing energy-source material inthe insert member in combination with the prosthetic or fixation devicedefining an actual ionizing energy delivery distribution field, theactual ionizing energy delivery distribution field having a similarconfiguration to the known ionizing energy-responsive profile of thetargeted tissue; and activating the ionizing energy-source material,thereby delivering the predetermined dosage of the ionizing energy fromthe ionizing energy-source material to targeted tissue within the knownionizing energy-responsive profile.
 7. A system for reducing infectiousprocesses and excess scar formation within targeted tissue, the systemcomprising: a prosthetic or fixation device for implantation andretention to natural bone tissue in proximity to the targeted tissue;and an ionizing energy-source material disposed in proximity to theprosthetic or fixation device, the ionizing energy-source material beingpart of the prosthetic or fixation device that is implanted, theionizing energy-source material being a non-chemical agent, the ionizingenergy-source material being non-radioactive at time of implantation,any dispensation of the ionizing energy-source material to the targettissue being minimal, the ionizing energy-source material enablingionizing energy treatment to reduce infection processes in the targetedtissue, the infectious processes being induced by surgical implantationof the prosthetic or fixation device, the ionizing energy treatmentbeing applied from the prosthetic or fixation device after implantation;whereby a predetermined dosage of prescribed ionizing energy to reducethe infection processes in the targeted tissue is determined by usingknown characteristics of the ionizing energy-source material and bycontrolling the placement of the ionizing energy-source materialrelative to the targeted tissue.
 8. A prosthetic or fixation device forreducing infectious processes and excess scar formation within targetedtissue for implantation into organic tissue or a prosthetic or fixationdevice, the prosthetic or fixation device delivering a dosage ofionizing energy to targeted tissue, the prosthetic or fixation devicehaving a function independent of ionizing energy delivery, theprosthetic or fixation device including an ionizing energy-sourcematerial, the implanted ionizing energy-source material enabling apredetermined dosage of ionizing energy treatment to be directed at thetargeted tissue after implantation, the ionizing energy-source materialbeing non-radioactive at time of implantation, the ionizingenergy-source material reducing infectious processes within the targetedtissue caused by the implantation of the prosthetic or fixation device,the dosage of prescribed ionizing energy to the targeted tissue beingpre-determined by applying known characteristics of the ionizingenergy-source material and by controlling the placement of the ionizingenergy-source material relative to the targeted tissue.
 9. A surgicalmethod for reducing infectious processes and excess scar formationwithin targeted tissue, the method delivering prescribed ionizing energyto the targeted tissue, the method comprising: introducing a prostheticor fixation device including an ionizing energy-source material, theprosthetic or fixation device and ionizing energy-source materialcomprising a closed system for implantation within a patient, theprosthetic or fixation device having a function independent of ionizingenergy delivery, the ionizing energy-source material being selected fordelivering a predetermined dosage of the ionizing energy from theionizing energy-source material to targeted tissue to reduce infectiousprocesses within the targeted tissue, the targeted tissue having a knownionizing energy-responsive profile, the profile of the targeted tissuebeing proximate to the implant site; and implanting the prosthetic orfixation device into organic tissue during a surgical procedure, theionizing energy-source material being non-radioactive at time ofimplantation, the ionizing energy-source material in combination withthe prosthetic or fixation device defining an actual ionizing energydelivery distribution field, the actual ionizing energy deliverydistribution field having a similar configuration to the profile of thetargeted tissue; and activating the ionizing energy-source material,thereby reducing infectious processes within the targeted tissue byapplication of the pre-calibrated dose rate, depth dose, and totaldelivered dose of prescribed ionizing energy, the infectious processesbeing induced by surgical implantation of the prosthetic or fixationdevice.
 10. The insert device of claim 1, wherein the ionizingenergy-source material is selected from the group consisting of yttrium,strontium, iridium, iodine, palladium, cesium, and technetium.
 11. Theinsert device of claim 2, wherein the ionizing energy-source material isselected from the group consisting of yttrium, strontium, iridium,iodine, palladium, cesium, and technetium.
 12. The surgical procedure ofclaim 3, wherein the ionizing energy is selected from a group consistingof luminescent energy, hyperthermic energy, and photo-light energy. 13.The surgical procedure of claim 4, wherein the ionizing energy isselected from a group consisting of luminescent energy, hyperthermicenergy, and photo-light energy.
 14. The implant system of claim 5,wherein the ionizing energy-source material is selected from the groupconsisting of yttrium, strontium, iridium, iodine, palladium, cesium,and technetium.
 15. The surgical method of claim 6, wherein the ionizingenergy-source material is selected from the group consisting of yttrium,strontium, iridium, iodine, palladium, cesium, and technetium.
 16. Thesystem of claim 7, wherein the ionizing energy-source material isselected from the group consisting of yttrium, strontium, iridium,iodine, palladium, cesium, and technetium.
 17. The prosthetic orfixation device of claim 8, wherein the ionizing energy-source materialis selected from the group consisting of yttrium, strontium, iridium,iodine, palladium, cesium, and technetium.
 18. A surgical method forreducing infectious processes and excess scar formation within targetedtissue, the method delivering prescribed ionizing energy to the targetedtissue, the method comprising; introducing a prosthetic or fixationdevice including an ionizing energy-source material, the ionizing energybeing selected from a group consisting of luminescent energy,hyperthermic energy, and photo-light energy, the prosthetic or fixationdevice and ionizing energy-source material comprising a closed systemfor implantation within a patient, the prosthetic or fixation devicehaving a function independent of ionizing energy delivery, the ionizingenergy-source material being selected for delivering a predetermineddosage of the ionizing energy from the ionizing energy-source materialto targeted tissue to reduce infectious processes within the targetedtissue, the targeted tissue having a known ionizing energy-responsiveprofile, the profile of the targeted tissue being proximate to theimplant site; and implanting the prosthetic or fixation device intoorganic tissue during a surgical procedure, the ionizing energy-sourcematerial being non-radioactive at time of implantation, the ionizingenergy-source material in combination with the prosthetic or fixationdevice defining an actual ionizing energy distribution field, the actualionizing energy delivery distribution field having a similarconfiguration to the profile of the targeted tissue; and activating theionizing energy-source material, thereby reducing infectious processeswithin the targeted tissue by application of the pre-calibrated doserate, depth dose, and total delivered dose of prescribed ionizingenergy, the infectious processes being induced by surgical implantationof the prosthetic or fixation device.